Help! Some kind of nodule appear on my fish!

[nono]

Have you tested your water?

Yes

If yes, what is your ammonia?

0

If yes, what is your nitrite?

I am sorry but I dont have test for nitrite

If yes, what is your nitrate?

15

If I did not test my water...

...I recognize that I will likely be asked to do a test, and that water tests are critical for solving freshwater health problems.

Do you do water changes?

Yes

What percentage of water do you change?

31-40%

How frequently do you change your water?

Every week

If I do not change my water...

...I recognize that I will likely be recommended to do a water change, and water changes are critical for preventing future freshwater health problems.

Hi. I am sorry if I keep asking for help from you guys about my fish health. But I need some help from you guys again.

It is about my indonesian tigerfish. Currently I have one datz that is around 35 or almost 40 cm I guess. Not sure about the exaxt biological ages, but I think I kept it since 2011 or early 2012. The tank water parameter is always stable except for the pH. 7,3-7,5. No ammonia. 27 degree celcius. And 15 for nitrate scale.

Today I just noticed that under its eye, there is a bump that looks kinda like a nodule and also some kind of lesion on its dorsal fin. Usually I give it shrimp as a staple food or sometimes cricket. But for these past two months, it refused them and only accepting live fish. So I give it some livebearer fish like platys.

What kind of medication can I give to my datz regarding the bump?

Thanks as always

 

[Dalfrey86]

Were the fish breed by you or at least in QT Prior to feeding?

 

[nono]

Were the fish breed by you or at least in QT Prior to feeding?

No. I bought it from my local fish store. But I dunno if it is a captive breed or wild caught. All I can remember is I bought it when it was only 5 or 6 cm long

No. For the last 4 years it always live in the same tank that is not a quarantine tank. At first it lived in 150 gal tank, but as it gets bigger and meanier, it shattered my tank bottom so I have to move it into smaller tank. It is 50 or 60 gal I tank. I know it is too small but I dont have any budget yet for repair my 150 gal tank. I only own another 130 is gal tank tank that is already occupied by one 50 cm asian aro that is also not friendly at all to other fish